[hebeldebel]

Hi,

I created a membrane, which is moved using the morphing option. The Morpher is "grid velocity" and the selected method is composite. A local cylindrical coordinate system was created in the middle of the membrane and its z axis is perpendicular to the membrane surface. In the "Physics Values => Grid Velocity" section of the membrane the local coordinate system was selected and although it is cylindrical, the submenu still shows X Y and Z Component. I set the Z Component to be a Field Function, which looks like this: " cos(${Time}*2*3.14/1)*0.0025 ". This works to move the membrane as a whole up and down. I would like to write this field function as a function of the radial distance from the z - axis of my local cylindrical coordinate system. How can I get the distance information into my field function?

[hebeldebel]

my post may have been a little unclear or confusing. How can I read out current coordinates with a field function? I know I can read out the time with ${Time} is there something like this for coordinates as well?

[hebeldebel]

$$Position and $$Centroid are mentioned in other posts, but I always get syntax error, when I try to make a value dependent upon the position:

$$Position("membrane")[1] always gives me syntax error